Horn loudspeakers of the sectorial diffusion type, and method for making said loudspeakers

Abstract

There is disclosed a method for making horn loudspeakers, of the sectorial diffusion type, characterized by the transformation, in order to operate under predetermined sectorial diffusion conditions, of a horn loudspeaker, predisposed for circular diffusion, comprising a horn provided with opposite walls the distances whereof increase according to a given law, from the axis of the horn on which the electroacoustic transducer is located, the transformation being carried out by neutralizing the space included between the walls and about the compression chamber associated with the transducer, and in the directions in which the diffusion is not desired, by using a substantially fibrous material and effective to absorb or deaden the acoustic energy or power.

I claim: 
     
       1. A loudspeaker of the sectorial diffusion type, which comprises two first opposite walls forming a horn, an electroacoustic transducer provided with a curved diaphragm tangentially contacting a third wall, said diaphragm and said third wall forming a structure, said two first walls being arranged in a direction essentially perpendicular to the vertical axis of said structure, and converging towards said structure, said diaphragm, said third wall and said horn forming a compression chamber, a mass of fibrous material in a sector of said compression chamber in an amount sufficient to absorb the acoustic power irradiated from the compression chamber in a predetermined direction in which diffusion or sound has to be deadened. 
     
     
       2. The loudspeaker according to claim 1 wherein said fibrous material is made of individually non-rigid fibers. 
     
     
       3. The loudspeaker according to claim 2 wherein the density of said fibrous material increases from the points thereof near to said electroacoustic transducer to the points thereof near the contour of said horn, whereby said horn is made sectorily attenuating or sound deadening. 
     
     
       4. An improved loudspeaker according to claim 1, 2 or 3 wherein the mass of said sound deadening material is formed by a plurality of modular portions located in the directions in which the diffusion is not desired or has to be attenuated.